Differential stage lift flow device



Nov. 4, 1941. A. BOYNTON 2,261,135

DIFFERENTIAL STAGE LIFT FLOW DEVICE Filed Dec. 8, 1959 ATTORNEYS.

Patented Nov. 4, 1941 UNITED STATES PATENT OFFICE 2,261,135 DIFFERENTIALSTAGE LIFT FLOW DEVICE Alexander Boynton, San Antonio, Tex. ApplicationDecember 8,1939, Serial No. 308,308

7 Claims.

My invention relates to devices for flowing wells by compressed air orgas.

The principal object is to discharge well liquid from wells by employingpressure fluid of relatively low value with resulting low gas-oilratios.

In accomplishing the foregoing object, another object is to employunusually great force in actuating the valves for the-purpose ofaccomplishing positive valve action and leak-proof valve seating.

A further object is to provide a valve that will not admit pressurefluid into the tubing in response to temporary high pressure areastherein.

Another object is to provide a durable flowing device of simpleconstruction which is easily adapted to flow through either the tubingor the casing.

A metallic bellows is anchored at one end and has a valve attached tothe other end within a chamber communicating between the interior andexterior of an eduction tube within a well casing. The free end of thebellows actuates a valve open at low difference in pressures within andwithout the eduction tube and closed at relatively great difference insuch pressures. The difference in these pressures is caused by arestricted passage limiting the flow of pressure fluid through thechamber surrounding the bellows. The outside of the bellows is exposedto the relatively high pressure on the high pressure side of the partialbarrier in the chamber which surrounds the bellows; while the inside ofthe bellows is exposed to the low pressure side.

I attain the foregoing objects by mechanism illustrated in theaccompanying drawing in which- Fig. l is a broken side view partly insection showing an installation of the devices in a well.

Fig. 2 is a longitudinal section through the preferred embodiment of theinvention for tubing flow.

Fig. 3 is a cross section on the line 33, Fig. 2.

Fig. 4 is a vertical section of a modified form of the invention adaptedfor casing flow.

Fig. 5 is a cross section on the line 5-5, Fig. 4.

Similar characters of reference are employed to designate similar partsthroughout the several views.

The difference in pressures obtaining at any time within the tubing andin the annular space la between the tubing and the casing will bereferred to as the difierential, that being the force which controls themovements of the valve 26a.

The column of well liquid which stands up in the tubing above the liquidlevel in the casing,

lar space la will be referred to as the upstanding column. Likewise, thecolumn of well liquid which stands up in the casing above the liquidlevel in the tubing, due

as the upstanding column.

It will be understood that liquid flow from the well will result fromintroduction of compressed air or gas into the upstanding column, whichwill be elongated by the expansion of the pressure fluid so introduced.v

The valve stem 26,the bellows 24, and all parts actuated by movement ofthe free lower end of said bellows will be designated as the movableassembly. It will be noted that this assembly is anchored proximate theupper end of the bellows and that the valve is attached to and isactuated by the movement of the free end.

- In Figs. 2 and 4, the body I 2, which may be cast or otherwisefabricated integrally with the tubular housing l2a, has a passage I 29of the same size as the tubing bore and aligned therewith. The bore I2cwithin the housing I2a has an annular space l2h between the bellows andthe wall of the bore. This clearance space may be such as 3 to inchwhile the over-all diameter of the bellows may be, for example, such as1% to 1 inches.

The bellows -24 is housed within the bore or chamber I20 and issupported at the upper end by an anchor l9 which may be engaged upon theslight internal ing and secured there by the valve seat member I8 whichis itself urged downward by the plug I 3, having threaded engagementwithin the upper end of the shell or housing lZa. The plug thus exerts asecuring force upon the gland ring M, the packing IS, the sleeve l6, andthe packing ll. These parts form a hermetic barrier between the annularspace la, Fig. 1, and the opening I21, except through the openings I2e'and l2e at the lower end of the housing; the passages l2h, I 9a, I80,[8b, l8a, lBd, Hic, and [6b. The size of these openings should be equalto or somewhat larger than the greatest clearance between the valve stem26 and the opening Mic. The valve 26a, formed upon the upper end of thestem 26, is adapted to prevent passage of pressure fluid through theopenings above mentioned by closing upon the seat l8d. when thedifferential compresses the bellows, as will be more fully exv due tothe presence of pressure fluid in the annu= plained. The lower end ofthe bellows is closed by a lower end connection 21 to which is secured acheck valve member 28. The open space 28c annular shoulder l2d of thehousunder the check valve 26b is provided in order to expose arelatively large area of the member 28 to the differential pressureentering through the passage l2e .below the check valve. The valve stem26, having its upper end positioned within the tapered bore I80, has itslower end secured at the free lower end of the bellows within said endconnection 21.

The tubular web |6a connecting the enlarged ends of the memberi6 andhaving the openings I60, provides two small annular chambers, one oneither side of the web, the chamber 16b being between the web and theshell l2a and the other chamber 16b being between the web and the memherit, as appears in Figs. 2, 3 and 4.

The bellows is secured upon its anchor is by the solder or weld 25 andsecured upon its lower end connection 21 by the solder or weld 25'. Thevalve stem 26 may be secured within an upward extension of the member 21by the weld 21a. This stem is closely slidable within the centralopening through the bushing 20, the packing 2i, and the gland ring 22.The coiled spring 23, preferably installed under some compression,engages between the upper extension of the member 21 and the gland ring22 and is freely slidable over the stem 26. The gland ring 22, siidablewithin the member l9, compresses the packing 2| by force of the spring23. Lateral openings 26b and the central opening 260 formed in the stem26 serve to equalize the pressure within the bellows with the pressurewithin the opening I80.

The check valve member 28 has a downward axial extension forming agovernor pin 26a. Said governor pin and check valve member 26, formedinto a check valve at 28b above the pin, has threaded engagement withinthe member 21.

The concavely tapered central opening ilc has, proximate the seat ltd, astraight portion a having a diameter only slightly greater, such asone-thousandth of an inch, than the outside diameter of the untaperedstem 26, which may be inch; while the diameter of the opening lBc at itslower end, may be such as 1: to /3 inch greater than the outsidediameter of the stem 26. The valve-like relation between the valve stem26 and the untapered portion a provides that the valve will not fly openwhen slugs of well liquid pass through the tubing 2 during the flowingoperation. A similar construction may be employed in Fig. 4.

The convexly tapered pin 28a proximate its upper end, may have onlyslight clearance, such as twoto flve-thousandths of an'inch, within theupper end of the passage l2e; while the lower portion of this pin willhave a clearance of 1 to /8 inch within this passage when the valve 26ais seated at Ild. It, therefore, will be observed that the clearancebetween the stem 26 and the opening I60 will be while the clearancebetween the passage in and the pin 26a is increasing, as the valve 260approaches its seat 16d, and vice versa. This arrangement for decreasingone opening while increasing the other will' allow the greatest flow ofpressure fluid into the upstanding column in the tubing at approximatelyone-half the differential required to completely seat the valve 26a. 1!it be desired to admit a greater amount of pressure fluid into thetubing at lower diflerentials, the pin 28a may be made smaller or whollyomitted.

The threaded opening l2e' is for connection of a testing means which maybe employed to check the valve adjustments.

It will be understood that the yieldable metallic bellows 24 and thespring 23 are adapted bore I and may be spaced at a distance such.

as to 1 away from the seat lBd. This valve is normally open as shown inFigs. 2 and 4, until closed by the differential, and has progressivelyless clearance around it while moving toward its seat ltd. The checkvalve 28 is lightly seated upon the lower extremity of the bore He inorder to prevent regress of the well liquid through the device atconclusion of the flowing operation. A check valve may be placed in thetubing proximately above the nipple 6 to complete the entrapment of suchliquid in the tubing.

In the operation of both forms of this device, there are three forceswhich govern the valve movements. The pressure fluid exerts the onlyforce constantly urging the valve toward its seat 18d; while theexpansive force of the bellows and spring, plus the force exerted by theupstanding column above the device, are the forces constantly urging thevalve away from its seat.

Manifestly, each of these forces is constant, and predetermined, exceptthe resistance of the upstanding column, which, of course, will vary ateach device, depending upon the distance between the device and the baseof the upstanding column. At the base of the upstanding column,

these opposing forces are equal, and the valve in a device there will beopen, as in Figs. 2 and 4. If, on the other hand, a device is positionedin the tubing at such distance above the base of the upstanding columnthat the portion of fluid in that column between its base and the deviceweighs, per square inch, exactly as much as the per square inch forcerequired to close the valve, then that valve will be just closed. Higherdevices will have their valves closed by increasing force withincreasing height of their positions in the upstanding column or aboveit. Each lower device will have its valve increasingly wider open as itsposition approaches the base of the upstanding column. a

The pressure fluid acts'upon the exterior of the bellows to compress it;whereas, the force of the upstanding column acts within the bellows toaid the spring and the bellows in resisting compression of the bellows.

In Fig. 2, the pressure fluid enters the chamber l2h to contact theexterior of the bellows via passages He, He, and the space 280, where itlifts the check valve member 26, and passes upwhich the well is beingflowed, the volume of well liquid, and other well conditions.

The rate of flow will be increased as the value of the pressure fluidemployed to accomplish flow is increased, and vice versa; although therate of increased flow, due to friction and thelaws governing energygiven off by expanding gases, will not be in direct proportion to theincreased value of the pressure fluid.

. For flowing the well through the tubing, reference is made to Fig. 1,wherein the tubing 2 of two diiferent sizes is joined together by theswaged nipple in the upper regions of the well. The casing head 4 isemployed to accomplish a hermetic seal between the well casing I and thetubing 2 proximately above the ground surface 8. The anchor string 1 mayextend from the nipple 6 to the bottom of the well 9. Well liquid entersthe tubing through the lateral opening in. The gun perforations ll admitinto the casing well fluid from the producing formation I 0. The flowdevices l2 are joined into the tubing by couplings 2a, the sloping endsI2b and I 2b being to guide the devices in passing deformitiesfrequently found in well casing.

If the well does not produce enough gas to flow it, pressure fluid maybe supplied into the annular space la through the line 3, but if thewell produces enough gas to flow it, the opening in the casing headoccupied by the line 3 may be closed by a plug, unless the line shouldbe needed to convey surplus gas from the well.

The casing flow line 40 and means for connecting it to the casing head,indicated by dotted lines, will be disregarded for the time being as ifnot shown.

The flow line 2b is supposed to be closed by an unshown valve andpressure fluid of proper value is assumed to be in the annular space la.

Now, to flow the well through the tubing, open the unshown valve in theflow line 2b. This will at once draw ofi the pressure fluid inthetubing,

, close all valves in the devices, and depress the well liquid from itsnormal level at A in both the tubing and the casing to the level Bwithin the annular space la. At the same time the well liquid rises inthe tubing to the level indicated at C. The device, next above thedepressed level B, will be open and discharging pressure fluid into theupstanding liquid column in the tubing, because the difi'erential therewill not be sufficient to close the valve 26a. This is true for thereason that the bellows and spring 23 will not compress enough to seatthe valve 26a unless the difl'erential be greater than the weight persquare inch of the liquid column between the valves, as

previously stated.

The globules of pressure fluid admitted into the upstanding columnexpand during their upward travel throughthe tubing and thereby elongatethe upstanding liquid column into and through the flow line 21).

As the liquid level is lowered in the annular space Ia, by and duringthe flowing operation, the valves in the upper devices will close inprogression downward, due to the downward movement of the level wherethe pre-dtermined differential necessary to close the valves obtains;while each lower valve will be open when uncovered by the receding wellliquid, due to the slight diiferential obtaining there.

The well, therefore, will flow by stages, and at relatively lowpressures with resulting comparatively low gas-liquid ratios due to thepower medium being metered to the load as previously explained.

The device illustrated in Fig. 4, which is an adaptation for casing flowof the device shown in Fig. 2, has all of its parts identical with thepreceding form, except that the body 29 and the governor pin member 30are somewhat diflerent from the corresponding parts I2 and 28,respectively, in Fig. 2.

The tubular body 29 in Fig. 4 is identical with the body i2 in Fig. 2,except for the opening 29b, which communicates between the passages I29and He, replacing the threaded opening He, and except for the otheropening 290 which communicates between the annular spaces la, Fig. 1,and IE1), Figs. 2 and 4, and further excepting the lower tapered-end29a.

The governor pin member 30 has the openings 30a to admit pressure fluidfreely from theopening 29b into the annular chamber l2h.

It will be understood that all parts not indicated as different fromthose in Fig. 2 will be the same as in Fig. 2. It will be alsounderstood that the force required to compress the bellows 24 and thespring 23 far enough to seat the valve 26a is, likewise, the same inboth constructions.

The path of the pressure fluid going out of the tubing is through thelateral opening 291),

through the annular space in the passage I2e,

bellows through the lateral opening 290, the annular space Ifib, theopenings llic, the annular space I641, the openings l8a, lb, 260, and26b.

The form of device illustrated in Fig. 4, adjusted and installed asstated for Fig. 2, will now be considered as spaced at intervals in thetubing string in Fig. 1 to flow the well through the easing, in place ofthe devices shown there for tubing flow.

The line 3 will be considered as replaced by a plug in the casing head4. The open line 4a; indicated by dotted lines as connected into thecasing head now will become the discharge conduit.

For flowing through the casing, the. induction tube 2 preferably will beall of one size and of somewhat smaller diameter than that employed forflowing through the tubing.

To initiate casing flow, pressure fluid of a similar value to thatpreviously mentioned for the tubing flow will be admitted through theline 2b into the tubing 2, it being understoodv that the well liquid isthen standing in both the tubing and the casing at the level indicatedat A. As the pressure fluid value increases in the tubing, the liquid inthe tubing will become depressed to the level indicated at D, while thetop of the upstanding liquid column in the casing will be at E. Thedevice next above the depressed liquid level in the tubing will be openand discharging pressure fluid into the upstanding column in the annularspace I a, and the well will flow through the casing in a manner sosimilar to that described for flowing through the tubing, as to requirelittle further explanation.

In flowing through the tubing, the pressure fluid enters the bellowschamber of the device illusing through the opening l2}; whereas, inflowing through casing the pressure fluid enters the bellows chamberthrough the opening 29b and enters the upstanding column in the annularspace In through the opening 290. Otherwise, the operation of bothdevices is the same.

manifestly, the valves in both terms of the invention may be formed oradjusted to pass more or less pressure fluid into the upstanding columnas different well conditions may require. Such change may beaccomplished either by increasing or decreasing the size of the openingsgoverning the admission oi the pressure fluid, or by changing theadjustment so as to cause the valve 26a to seat at a higher or lowerdifferential. Similar results may be obtained by increasing ordecreasing the value of the pressure fluid,

as previously indicated.

It is also apparent that the valves in diflerent devices of aninstallation may be so made as to differ from each other in thedifferential required to close them, as well in the volume 01' pressurefluid that will pass through them at the same pressure fluid value. Themanner of progression in providing such changes in the valves will besuggested by well conditions to those skilled in the art.

The cross sectional area of the bellows being many times greater thanthe cross sectional area of thevalve, as shown, it is evident that theforce employed to seat the valve will be many times greater than thatemployed to seat valves having the same area as that of their seatsexposed to the actuating force, as is now the practice in devicesemployed for similar purposes.

The invention as herein illustrated and described is maniiestly subjectto many changes in construction and arrangement of parts which will bewithin the scope and purpose of the stated objects and appended claims.

What is claimed is:

1. In a stage liIt device, a valve body, a vertically extending housingthereon having openings at its opposite ends leading respectively to theinterior and the exterior of said body for the passage of a pressurefluid therethrough, a bellows diaphragm in said housing anchored at itsupper end to the housing and having its lower end tree, a lower valvconnection closing the lower end of said bellows diaphragm, a checkvalve on said connection adapted to seat in the lower opening in thehousing, a valve seat adjacent the upper end of said housing, said seatbeing connected with the upper opening, a tubular cylindrical valve stemconnected with said lower valve connection and normally projectingupwardly through the upper end of the bellows diaphragm to a pointadjacent said upp r seat, a'valve on said stem, said stem having lateralports therein within said diaphragm whereby pressure of fluid at saidupper opening may be exerted within said bellows diaphragm, and passagesupwardly from said lower opening about said bellows to said upperopening.

2. In a stage lift device, a valve body, a vertically extending housingthereon having openings at its opposite ends leading respectively to theinterior and the exterior of said body for the passage of a pressurefluid therethrough, a bellows diaphragm in said housing anchored at itsupper end to the housing and having its lower end free, a lower valveconnection closing the lower end of said bellows diaphragm, a. checkvalve on said connection adapted to seat in the lower opening in thehousing, a valve seat adjacent the upper end of said housing, said seatbeing connected with the upper opening. a tubular cylindrical valve stemconnected with said lower valve connection and normally projectingupwardly through the upper end or the bellows diaphragm to a pointadjacent said upper seat, the upper end of said cylindrical stern beingtapered to form a valve to engage said seat. a cylindrical area belowsaid seat into which said stem slidably engages to prevent sudden surgesoi fluid past said valve, a passage through said stem to the interior orsaid diaphragm, the outer surface of said'bellows being exposed to fluidpressure from said lower opening when said check valve is unseated.

3. In a stage lift flow device for Wells, a valve body having anopening, a housing on said valve body one end of which communicates withsaid opening, the other end of said housi g having an opening to theoutside, an upper valve seat member in said housing, an upwardly taperedrecess in said member forming a seat connected with the uppermost ofsaid openings, a bellows diaphragm in said housing below said valve seatmember, an anchor therefor at the lower end of said seat member, saidanchor having passages outside said bellows diaphragm to said recess, atubular valve stem, a support therefor closing the lower end of saidbellows diaphragm, said stem fltting slidably through said anchor andadapted to engage said seat, said stem having openings therein, andmeans movable with said diaphragm to close the other of said openingswhen said valve is fully opened.

4. In a stage lift flow device for wells, a valve body having anopening, a housing on said valve body one end of which communicates withsaid opening, the other end of said housing having an opening to theoutside, an upper valve seat member in said housing, an upwardly taperedrecess in said member forming a seat connected with the uppermost ofsaid openings, a bellows diaphragm in said housing below said valve seatmember, an anchor therefor at the lower end of said seat member, saidanchor having passages outside said bellows diaphragm to said recess, atubular valve stem, a support therefor closing the lower end of saidbellows diaphragm, said stem fitting slidably through said anchor andadapted to engage said seat, a fluid conduit from the uppermost of saidopenings to the interior of said diaphragm, and means operating whensaid bellows is iully expanded to close the other 0! said openings.

5. In a stage lift flow device for wells, a valve body having anopening. a housing on said valve body one end of which is connected withsaid opening, the other end of said housing having an opening to theoutside. an upper valve seat memher in said housing, an upwardly taperedrecess in said member forming a seat connected with the uppermost ofsaid openings, a bellows diaphragm, an anchor therefor at the lower endof said seat member, said anchor having passages outside said bellowsdiaphragm to said recess, a lower connection closing the free end ofsaid bellows diaphragm, a valve stem thereon extending upwardly throughsaid anchor to said recess, a valve on the upper end thereof, saidrecess being formed to choke the passage of fluid thereby when saidvalve is positioned near said seat, means iurnishing a passage for fluidfrom said uppermost opening to the interior of said diaphragm, and meanstoclose the other 01 said openings but operating in response to fluidpressure to open and permit passage of fluid through said housing. I

6. A valve body, a housing. there0n, a check valve 'seat at the lowerend of said housing surrounding an inlet passage to said seat fromexteriorly of the valve body, a valve seat connection in the upper endof said housing, a removable plug in the upper end oi said housing tosecure said connection rigidly in position, an upwardly tapering valveseat in said connection, said seat being connected y a passage to theinterior of said valve body. a valve stem, valves thereon adapted tomove into engagement with.

said seats, means supporting both said valves and operating in responseto difierential pressures within and outside said valve body to movesaid valves to open one and close the other simultaneously and meanstending to hold one of said valves normally closed upon the check valveseat.

7. A valve body, a housing thereon, a check valve seat at the lower endof said housing surrounding an inlet passage to said seat, a valve seatconnection in the upper end of said housing. a removable plug in theupper end of said housing to secure said connection rigidly in position,an upwardly tapering valveseat in said connection, said seat beingconnected by a passage to the interior of said valve body, a valve stem,

a plug at the lower'end of said connection, said stem having a closesliding fit through said plug, valves on said stem adapted to engagesaid seats, fluid pressure operated means to move said valve stem andvalves, and a tapered Bovemor pin on the lowermost of said valvesprojecting into said lower opening.

ALEXANDER BOYNTON.

